The Pontiac Grand Prix featuring the 3.8-liter supercharged engine comes equipped with two drive belts. The primary serpentine belt functions as a serpentine belt does on most cars. The secondary belt--the supercharger belt--provides the additional power for the supercharger on demand. This belt is located on the outside of the pulley system and is the easiest one to remove and replace. To replace the primary serpentine belt, the supercharger belt needs to be removed first, so whether you need to replace the supercharger belt or simply remove it to get to the primary, follow these steps.
Open the hood and approach the engine from the passenger side of the Grand Prix to access the supercharger belt.
Locate the tensioner pulley for the supercharger. It is below the supercharger pulley and towards the front of the engine compartment.
Place the 15-mm box-end wrench onto the tensioner pulley bolt and move the wrench clockwise to release tension on the supercharger belt. While holding the wrench in position, remove the belt from the supercharger pulley and then slowly release the tensioner pulley back into its seated position.
Compare the size of the old belt to the new one to ensure you've purchased the correct sized replacement belt.
Route the supercharger belt according to the belt routing diagram, starting with the crank pulley at the very bottom and working your way up toward the supercharger pulley. Make sure the ribs of the belt are seated properly inside the grooves of the pulleys. The smooth side of the belt goes against the smooth idler pulleys and the ribs of the belt must wrap around the grooved pulleys.
Hold the belt in position with one hand as close to the supercharger pulley as you can. Place the wrench onto the tensioner pulley and move it clockwise again to relieve the tension. This repositioning of the tension pulley will allow you just enough room to slide the belt onto the supercharger pulley. There will be little extra slack. Do not force the belt onto the pulley. If there doesn't seem to be enough slack, check the routing and pulley seating position of the belt.
Start the engine to make sure the belt is running smoothly along the pulley system. Make sure to remove the wrench and old belt from the engine compartment before starting up the engine.
